Vulnerability · Published Oct 27, 2026 · Assigned by hackerone
CVE-2025-64394
Medium 4.3
In plain English
A medium-severity security flaw in Backup for Microsoft 365 from Veeam. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.1% (higher than 1% of all known vulnerabilities).
Severity (CVSS 4.0)4.3Medium
Exploit odds (30 days)0.1%top 98.8% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
A vulnerability allowing a low-privileged local user to write arbitrary files with SYSTEM privileges during the installation of Veeam Backup for Microsoft 365, which can lead to privilege escalation or denial of service.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Veeam | Backup for Microsoft 365 | 8.0 – through 8.6.0.1102 |
Weakness: CWE-1386 · Vector: CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:A/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N